The polarization of inclusive J/ψ and Υ(1S) produced in Pb–Pb collisions at √sNN = 5.02 TeV at the LHC is measured with the ALICE detector. The study is carried out by reconstructing the quarkonium through its decay to muon pairs in the rapidity region 2.5 < y < 4 and measuring the polar and azimuthal angular distributions of the muons. The polarization parameters λθ, λφ and λθφ are measured in the helicity and Collins-Soper reference frames, in the transverse momentum interval 2 < pT < 10 GeV/c and pT < 15 GeV/c for the J/ψ and Υ(1S), respectively. The polarization parameters for the J/ψ are found to be compatible with zero, within a maximum of about two standard deviations at low pT, for both reference frames and over the whole pT range. The values are compared with the corresponding results obtained √s = 7 and 8 TeV in a similar kinematic region by the ALICE and LHCb experiments.
Eser Adı (dc.title) | First measurement of quarkonium polarization in nuclear collisions at the LHC |
Yayın Türü (dc.type) | Diğer |
Yazar/lar (dc.contributor.author) | KARASU UYSAL, Ayben |
Yazar/lar (dc.contributor.author) | ALICE Collaboration |
Atıf Dizini (dc.source.database) | Wos |
Atıf Dizini (dc.source.database) | Scopus |
Yayın Tarihi (dc.date.issued) | 2021 |
Kayıt Giriş Tarihi (dc.date.accessioned) | 2022-03-05T13:20:36Z |
Açık Erişim tarihi (dc.date.available) | 2022-03-05T13:20:36Z |
Özet (dc.description.abstract) | The polarization of inclusive J/ψ and Υ(1S) produced in Pb–Pb collisions at √sNN = 5.02 TeV at the LHC is measured with the ALICE detector. The study is carried out by reconstructing the quarkonium through its decay to muon pairs in the rapidity region 2.5 < y < 4 and measuring the polar and azimuthal angular distributions of the muons. The polarization parameters λθ, λφ and λθφ are measured in the helicity and Collins-Soper reference frames, in the transverse momentum interval 2 < pT < 10 GeV/c and pT < 15 GeV/c for the J/ψ and Υ(1S), respectively. The polarization parameters for the J/ψ are found to be compatible with zero, within a maximum of about two standard deviations at low pT, for both reference frames and over the whole pT range. The values are compared with the corresponding results obtained √s = 7 and 8 TeV in a similar kinematic region by the ALICE and LHCb experiments. |
Tek Biçim Adres (dc.identifier.uri) | http://hdl.handle.net/20.500.12498/5369 |